Corrosion resisting built-up closure and method of making same



no Z |II|L .I 6 7t 1 z 4 R r Mg. 1 5 M 3 M m w wn 1 F 2 z 0 WA m m R f m v a no m a .m z a a g A 5 W. s fi M 1 m W M. 1 v.. Q J & V w m a a z 5 z 1 00 Z a v 4 0 0 2 Z d 4 W 4 J |v A ril 16, 1940. F. M. LAMBERT CORROSION RESISTING BUILT-UP CLOSURE AND METHOD OF MAKING SAME Filed April 21', 1938 Patented Apr. 16, 1940 v 1 CORROSION RESISTING BUILT-UP oLo- SURE AND- METHOD OF MAKING SAME "Francis M. Lambert, Narberth, Pa., assignor to Heintz Manufacturing Company, a corporation of Pennsylvania.

' UN TED] STATES PATENT OFFICE Application April 21, 1938, Serial No. 203,352 v 8 Claims. (c1. 29-148) This invention relates to corrosion resisting by a. corrosion resisting substance by hot proc built-up or assembledolosu res, of a typesuitable essing and any fullness caused in the panel porfor use as ship doors or hatch covers and the tion thereof by the temperature of the hot procmethod of making same. Y ess is removed by an embossing operation with- In fabricating aship door or hatch cover of out cracking or. otherwise injuring the coating 5 metal, such as wrought iron, steel, or the like, thereon. I it is important that the built-up structure be Additional objects and advantages of the inprovided with a protective coating or otherwise vention will become apparent upon consideration treated to provide it with corrosion resisting surof the following detailed description and ap- 10 faces. In applying or formingthe protective pended claims whenread in connection with the 10' coatingor surface by some of the more desirable accompanying drawing, in which: methods, such as'hot galvanizing or a form of Fig. 1 is a view in elevation'with parts broken the well known black oxidizing process, it is away of a. door or hatch cover construction emnecessary to subject the built-up structure to relbodying the invention as viewed toward the in- 5 atively high temperatures varying somewhat with ner face thereof; 1 the method used and the type of coating or treat- Fig. 2 is an enlarged sectional-view of the edgement applied. For example, in hot dip galvanizportion thereof taken on line 2-2 of Fig. 1; ing a temperature of at least 790 F. is required. Fig. 3 is an enlarged'sectional view-of another Likewise,- in some cases, as for example when emportion of the door or hatch cover taken on line 'ploying aluminum and various other non-ferrous 33'of Fig. 1; and e p 1 20 metals or alloys as the construction material, it Fig. 4 is an enlarged sectional view of a poris sometimes desirable to subject the fabricated tion of the panel indicating a protective coating structure to a heat treatment to relieve strains thereon. set up'in welding or to otherwise improve the Fi'gsLl to 3 of. the drawing show, for'purposes 5 properties of the metal. of illustration,- a built-up ship door constructed W e b p Structures, v b e Subject in accordance with my invention which is able to relatively high temperatures, suchas encountto resist great pressure without buckling and ered in h p galvanizing, p yin f mol which lends itself readily to hot galvanizing and metal, black oxidizing Various forms of heat similar coating processes, as well "as to other treatment, the thinner sheet metal panelpormotective urfadin'g treatments employing 30 tions of the built-up structure have heretofore elevated temperatures 1 j th upporting been found to have, an undesired fullness after frame may take different forms; I shall illustrate completion of the hot processing. This fullness w invention by fer t a construction of the sheet metal portions may arise because of bodying frame. f the'type. dgslclosed in Design the quicker cooling of the thinner sheetmetal Patent No. 118,162. The door construction comportions as compared with h heavier section of prises a skeleton frame formed of a continuous the Supporting frame members i the result .marginal stiffening member I!) and a plurality of that the sheet metal in cooling from the relatively fireinfoming ribs h the ends thereof-Welded high temperature tends to contract o h more to the inner surface of the marginal stiffening 4 rapidly than the frame as to place it under astate member m A relatively n sheet f Ordinary 40 of s e when members carbon steel or other suitable metal. is secured on' have cooled the thin panel Portlon W111 tend to one side of the skeleton frame and turned about bulge and present the undesirable fullness. the peripheral edge of magma] member to One of the objects of the present invention is f 1 a I or a nel portio M. B, w J of ex myle. the to provlde new method of makmg fabncated (10;: illi js trated isr ade up of margi al? i fen- 45 closures of the type suitable for use as ship doors V or hatch covers, wherein the surfaces thereof g member "'{F' rgmjurcmg halvmg are rendered corrosion resistant and any fullness thlckns of a a panel h thlckness occurring in the panel portion thereof is reso moved. =The margmal stiffen ng; member H) is shown Another object of the invention is to provide asincludmg a pair of flang and 18 x nd g an improvementin the manufacture of corrosion at right angles each other andgenemuy resisting'built-up closures having panel portions .Sembling an L in I0S' SeCti0n. The outward and supporting frame portions 'ofuneoual cross- "face of the flange '5 is provided with laterally 5a sectionwherein the surfaces thereof are coated extending projection H suitably p d from the 55.

flange [8 so as to cooperate therewith in retaining the usual sealing gasket, as more fully hereinafter described. The projection II also serves to stiffen the frame. The free end of the flange I6 is thickened and rounded, as at I3 to further nels 22 at spaced intervals longitudinally thereof, whereby liquid, molten metal or like substance may readily drain from pockets and inter- I stices presented by the fabricated structure when subjected to acoating process tobe hereinafter described. The edge portions 24 between the channels 22 may be secured by arc welding in a staggered manner 'to the panel 14, as shown at 25 in Fig. 1, or may be Welded to the panel M on both sides of the T stiffener. I

The panel 14 besides being welded to the portions 2% of the ribs i2 is secured by a continuous seam weld 21 to the adjacent surface of the flange I8 of the marginal member I U. The outer edge of the panel is turned at right angles about the pe ripheral edge of the flange l8 and extends parallel to the flange it for a short distance where 'it is turned inwardly at 28 toward the flange 16 to form therewith a channel 30 to receive a sealing gasket 32. The laterally extended projection H on the outward face of flange. l6 cooperates with the turned edge 28 to retain the gasket 32 in the channel 30.

Additional arc welds are made as at 34 between the panel M and the upper inner edge of the marginal stiffening member, as shown in Fig. 2. These welds may be intermittent or continuous. Welds 35- are also provided between the flange portions 26 of the ribs l2 and the adjacent flange Before treating the surfaces of the built-up closure, it is of course important that the surfaces be cleaned of all rust, scale, grease, and dirt. Such cleaning may be effectively performed by the well known pickling bath. The passages formed by the cut-outs 22 in the reinforcing ribs I2 permit the liquid of the bath, loosened dirt andscale to drain from pockets or interstices presented by the shape of the ribs [2 and their interconnected relation with the stiffening member l and panel M. After removing the built-up closure from the pickling bath and associated washing and drying process, the closure may be sprayed with a coating of molten metal, hot dip galvanized, or otherwisetreated, such as' by one of the well known forms ;of black oxidizing, to render the surfaces thereof resistant to corrosive influences. Where a protective coating is applied, such as by immersing the structure in a bath of coating material, the passages formed by'the channels 22 also function to enable surplus coating material to drain effectively from the fabricated structure.

The built-up closure is subjected during hot dip galvanizing and similar coating processes to 7 heat of a degree and amount sumcient to cause considerable expansion of the metal of which the closure is made. being relatively thin, colls first and shrinks until In cooling, the panel portion.

1t reachestatmospheric temperature. The heavier frame and rib members cool more slowly. As they .cool they likewise shrink, and as a consequence the whole structure is reduced in size. As these heavier members contract, the panel embraced by the stiffening frame cannot be compressedon account of the thinness of the sheet of metal 01' whichit is made, and consequently it buckles or bulges and shows an undesirable fullness.

This fullness of the panel portions, while not weakening the door construction to any appreciable extent; presents an undesirable appearance. To'remove this fullness .of the panel portions, an embossment either in the form of paneling, beading, corrugations, or other decorative relief, may be impressed into the panel. In the embodiment illustrated, a form of paneling is shown comprising a plurality of rectangular depressions 40 impressed into thepanel M on the inner face thereof. Such paneling, however, as well as other forms of embossment,-may be impressed into the pane M'from the outer face thereof, if desired.

Where the embossment is impressed after "the hot coating process, such as hot galvanizing, for example, care must be taken not to crack the coating 33, Fig. 4, at the edges of the paneling or other form of embossment. 'I may avoid crack ing the galvanizing or other coating, as the case I may be, by forming a die with surface portions of rubber or similar substance in accordance to the relief desired. The edges of the die being resilient V operate to spread the strain of the embossing operation so as not to injure the coating contained on the surfaces-of the panel. However, if the edges of the die are suitably rounded, the rubber facingmay be omitted Thus, when the built-up product hasbecome sufficiently cooled. and the coating hardened, it may b'eplaced in asuitable die and depressions or other relief impressed into the panel to remove the fullness therefrom without danger of crackingjthe coating In a door made of members of the; relativethicknesses referred to in the specific example hereinbefore mentioned, the undue fullness :will be satisfactorily removed by producing spaced embossed areas A" in depth.

ginal stiffening member Ni and welded or otherwise secured to the inner side thereof and the packing 32' omitted. 3

Since many changes can be made in the above turned about the peripheral flange 18 of the mar- Y construction and method, and as many apparently widely differing embodiments of this invention can be made without departing from'the scope thereof, all matter contained in the above description or shown in the drawing is to be interpreted as illustrative and not as restrictive,

. except in so far as is necessitated by the prior art and the scope of the appended claims.

I claim: y

1. In the manufactureof a built-up metal ship door or hatch cover comprising a panel portion and a supporting frame, in which said framecomprises elements of relatively heavy. cross section as compared with said panel, the steps which comprise'forming a corrosion resisting section as comparedwith said panel, the steps I which comprise immersing the door structure, after it has been built up, in a bath of molten metal and thereby forming a protective coating over the entire door assembly, allowing the door to 'cool to atmospheric temperature, and thereafter embossing said panel to remove the bulges or fullness developed therein in the course of the cooling of the door from the coating temperature.

3. Inthe manufacture of a built-up metal ship door or hatch cover comprisinga panel portion and a supporting'irame, in which said frame comprises elements of relatively heavy crosssection as compared with said panel, the steps which comprise immersing the door structure, after it has been built up, in a bath of molten zinc and thereby forming a protective coating over the entire door assembly, allowing the door to cool to atmospheric temperature, and thereafter subjecting said panel to a controlled embossing' treatment to remove bulges or fullness Ideveloped therein in the course of the cooling of the door from the coating temperature.

4. In the manufacture of a built-up metal ship '1 door or hatch cover comprising a panel portion and a'supporting frame, in'which said frame comprises elements of relatively heavy crosssection as compared with said panel, the steps which comprise forming a corrosion resisting surface on the door structure, after it has been built up, by a surface treatment involving'heating of the structure throughout to a temperature of at least about 790 F., allowing the structure to cool to atmospheric temperature,- and thereafter confining said panel in a resilient embossing-die to produce embossed or raised areas thereon and thereby remove the undesired fullness developed] in said panel in-the course of the cooling of the door from the temperature of the surfacing treatment.

5. In the manufacture of a built-up metal ship door or hatch cover comprising a panelportion and a supporting frame, in which said frame comprises elements of relatively heavy cross-section as compared with said panel, the steps which com-J prise subjecting the door structure, after it has been built up, to a hot dip metal coating treatment in which said structure is brought to the temperature of the coating bath, allowing the door to cool to atmospheric temperature, and thereafter confining said panel in a resilient embossing die to produce thereon a plurality of reg- "ularly spaced raised areas and thereby removing the undesired fullness developed in said panel in in the course of the cooling of the door from the temperature of the coating bath.

6. In the manufacture of abuilt-up metal ship door or hatch cover comprising a panel portion and a supporting frame, in which said framecomprises elements of relatively heavy cross-section as compared with said panel, the steps which comprise assemblying said panel and frame into an integral built-up structure, forming a corrosion resisting surface on said built-up structure by a surface treatment in which said structure, is

' brought to a temperature of at least about 790 F., allowing the door to cool to atmospheric temperature, and therafter subjecting said panel to a controlled embossing treatment to produce thereon a plurality of spaced raised areas sufficient to remove the fullness caused in said panel by the heat treatment while at the same time preventing cracking of the corrosion resisting sur- 7 face.

'7. A built-up metal closure suitable for use as a ship door or hatch cover, comprising'a relatively thin metal paneland a relatively thick marginal stiffening member secured to said panel adjacent the edge thereof, said built-up closure having a corrosion resisting surface extending continuously over the entire structure and formed by a surface treatment in which said built-up structure is heated to at least 790 F., said panel also being characterized by the metallographic structure characteristic of, a material of like composition that has been stretched during'cooling'from a temperature of at. least 790 F., and i.- being further characterized by a plurality of spaced embossed areas formed thereon after the surface treatment has been applied.

' 8.- A built-up metal closure suitable for use as a ship door or, hatch cover, comprising'arelatively thin rneta1 panel and a relatively thick marginal stiffening member secured to said panel adjacent the edge thereof, said built-up closure having a coating of corrosion resisting metal thereon extending continuously ,over the entire assembly of the elements thereof and havingbeen applied by a hot dip treatment, said panel being characterized by the metallographic structure characteristic of a material of like composition that has been stretched during cooling from a temperature ofat leastabout 790 F. and being further characterized by a plurality of spaced embossed areas formed thereon after the hot' dip coating treatment.

' FRANCIS M. LAMBERT. 

